Coexistence of Chirp-Spread Waveforms and OFDM Over a Single Frequency Band

OCDM is a superposition of mutually orthogonal, phase- and amplitude-modulated chirp waveforms which share the time and the bandwidth. Given the chirp waveform's known robustness against multipath effects and Doppler shift, OCDM is considered one of the promising waveforms for channels with high delay and Doppler. However, since the spectrum of each chirp waveform in OCDM occupies the entire signal bandwidth, the only way to adjust it is by modifying the sampling frequency, which makes it challenging for OCDM to coexist with the widely used OFDM in a single network. In this paper, we consider an OCDM-like waveform with an easily adjustable signal bandwidth to coexist with OFDM in a single network over a single frequency band. This paper also includes BLER performance evaluation of the waveform we have considered.